Filter-bottom.



No. 667,005. Patented Jan. 29, I901. J. DAVIS.

FILTER BOTTOM.

(Application filed Sept. 28, 1900.!

2 SheetsSheet I.

(No Model.)

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FILTER BOTTOM. (Application filed Sept. 28; 1900.

2 Sheets Shee t 2.

(NO Model.)

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"rates UNITE JOHN DAVIS, OF PITTSBURG, PENNSYLVANIA.

FILTER-BOTTOM.

SPECIFICATION -01'.tI] i;l'J.,*' part Of Letters Patent NO. 667,005, dated January 29, 1901.

Application filed September 28, 1900. Serial No. 31,398. (No model.)

To all whom it may concern:

Be it known that I, JOHN DAVIS, .a citizen of the United States, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Filter-Bottoms; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the My invention relates to filters for purifying liquids, such as water, has especial reference to that class of filters in which a granular bed is used for filtering the water, and has for its object a filter-bottom on which the granular bed rests; and it consists in certain improve ments in construction, which will be fully disclosed in the following specification and claims.

In the accompanying drawings, which form part of this specification, Figure 1 represents a top plan of a filter-bottom embodying my invention designed for use in cylindrical filters of comparatively small diameter; Fig. 2, a transverse sectionof the same on line 2 2, Fig. 1; Fig. 3, a perspective showing the filter-bottom applied to an angular filter and on an enlarged scale; Fig. 4, a vertical section on line 4 4, Fig. 3; and Fig. 5, a like view on line 5 5, Fig. 3.

Reference being had to the drawings and the designating characters thereon, 1 indicates the base of the filter-bottom and may be circular, as shown .in Figs. 1 and 2, or rectangular, as shown in Figs. 3, 4, and 5, or of any other preferred form. In the circular form for use in filters of comparatively small diameter the base is provided with slots 2, which may be radial and tapering toward the center, as shown in Fig. 1, or the taper may be omitted and the sides of the slots made parallel, the purpose of the elongated openings 2 are openings 3, preferably circular, as

Upon the base are placed sheets or layers of wire-cloth, preferably brass or aluminium bronze, the lower layer 4 and the upper layer 5 being coarse mesh and the intermediate layer 6 of fine mesh to prevent waste of the filter-bed through the bottom. The strata of wire-cloth are secured to the base 1 by clamping-plates '7, resting on the cloth, and through which pass bolts or rivets 8 and engage the base to prevent displacement by the upward flow of water passing through the bottom in cleansing the filter-bed. The elongated and the circularopenings should be so graduated that they will afford a ready flow of the water admitted for cleansing the filter-bed with the minimum of friction or resistance in its passage through the base, so that its maximum force may be expended upon the granular bed to lift and agitate the same.

In large filters, whether cylindrical or rectangular in form, the base-plate is made in sections 9, as shown in Figs. 3, 4, and 5, and the plates separated to form the elongated openings '10, which extend across the filter from side to side or wall to wall. The strata of wire-cloth, as described, are then stretched across the entire bottom plates, covering the elongated openings 10, and the cloth and the base-plates secured together by the clampingplates 7 and bolts 8, and the bolts on the ends of the plates extend through the flanges 11 on which the bottom rests. The plates or bottom also rest upon supports 12,which cross the filter at right angles with plates, and below the bottom is a chamber 13 for filtered water.

The circular bottom shown is Figs. 1 and 2 is provided with a step 14 to support the shaft of an agitator.

Having thus fully described my invention, what I claim is- 1. A filter-bottom having a perforated base, and wire-cloth arranged in separate layers over said base with a layer of fine mesh interposed between layers of coarse mesh, and clamping-plates resting upon the upper surface of the bottom and secured to the base covering said openings with a layer of fine mesh interposed between layers of coarse mesh, and clamping-plates for securing the wire-cloth to the base.

In testimony whereof I affix my signature in presence of two Witnesses.

JOHN DAVIS.

Witnesses:

WM. W. WISHART, ALEXANDER WISHART. 

